Ski boot heel binding

ABSTRACT

In a heel binding of the type having elongated body member having a forward heel boot holding means, a body member swingable relative to a base member about a rearward horizontal pivot axis substantially perpendicular to the axis of the ski runner substantially parallel to the top face of the runner, whereby the heel boot holding means is pivoted from a holding position in which the heel holding means is substantially abutting the top face of the runner, to a release position in which this heel holding means is raised from and inclined relative to the top face of the runner, the improvement including: (a) a single coil spring carried by one of the body members and the base member operating along a zone of action; (b) a V-frame connecting means positioned intermediate the rearward pivot axis of the binding and the heel-holding means in operative contact with the single coil spring, and including first and second leg means carrying cooperative broad-contacting, complementary surface means at their swingably engaging surfaces to each other, one of the leg means also carrying thereto a substantially disconnectably connecting L-shaped cam surface aligned with the zone of action of the spring; (c) linking means for connecting the first and second leg means to the body member and the base member, respectively, a pair of horizontal pivot axes, and including a stationary pin means disconnectably positioned with respect to the disconnectably connecting L-shaped cam surface on the one leg means to normally prevent pivotal tilting of the body member relative to the base member, but being adapted to release from said cam surface allowing relative angular displacement of the first and second leg means when subjected to either of two load conditions corresponding to (i) an accident condition or (ii) a manual release condition above the operational release level of the binding; (d) the single coil spring adapted to undergo axial movement to release the stationary pin means of said linking means from the disconnectably connecting cam surface carried on the one leg means, by cooperative angular movement of said leg means in response to a load condition resolvable into an antibias component force acting along the zone of action opposite to the normal bias force of the single coil spring; (e) after release of the stationary pin means of the linking means from the cam surface, continued depthwise displacement of the horizontal pivot axis being aided, at least in part, by the normal bias force of the single coil spring until the release position of the heelholding means is achieved, after the release position is attained and the load condition acting on the binding is terminated, the release position being maintained by the normal bias force of the single coil spring.

United States Patent Berlenbach [15] 3,643,977 Feb. 22, 1972 [54] SKIBOOT HEEL BINDING [72] Inventor: Bernard E. Berlenbach, Mill Valley,Calif.

[73] Assignees: Ski Free Company, Mill Valley, Calif; M.

A. Miller Manufacturing Co.

[22] Filed: July 23,1970 [21] Appl.No.: 57,696

Primary ExaminerLeo Friaglia Assistant Examiner-Robert R. SongAttomeyl-l. D. Messner 57 ABSTRACT In a heel binding of the type havingelongated body member having a forward heel boot holding means, a bodymember swingable relative to a base member about a rearward horizontalpivot axis substantially perpendicular to the axis of the ski runnersubstantially parallel to the top face of the runner, whereby the heelboot holding means is pivoted from a holding position in which the heelholding means is substantially abutting the top face of the runner, to arelease position in which this heel holding means is raised from andinclined relative to the top face of the runner, the improvementincluding: (a) a single coil spring carried by one of the body membersand the base member operating along a zone of action; (b) a V-frarneconnecting means positioned intermediate the rearward pivot axis of thebinding and the heel-holding means in operative contact with the singlecoil spring, and including first and second leg means carryingcooperative broad-contacting, complementary surface means at theirswingably engaging surfaces to each other, one of the leg means alsocarrying thereto a substantially disconnectably connecting L- shaped camsurface aligned with the zone of action of the spring; (0) linking meansfor connecting the first and second leg means to the body member and thebase member, respectively, a pair of horizontal pivot axes, andincluding a stationary pin means disconnectably positioned with respectto the disconnectably connecting L-shaped cam surface on the one legmeans to normally prevent pivotal tilting of the body member relative tothe base member, but being adapted to release from said cam surfaceallowing relative angular displacement of the first and second leg meanswhen subjected to either of two load conditions corresponding to (i) anaccident condition or (ii) a manual release condition above theoperational release level of the binding; (d) the single coil springadapted to undergo axial movement to release the stationary pin means ofsaid linking means from the disconnectably connecting cam surfacecarried on the one leg means, by cooperative angular movement of saidleg means in response to a load condition resolvable into an antibiascomponent force acting along the zone of action opposite to the normalbias force of the single coil spring; (c) after release of thestationary pin means of the linking means from the cam surface,continued depthwise displacement of the horizontal pivot axis beingaided, at least in part, by the normal bias force of the single coilspring until the release position of the heel-holding means is achieved,after the release position is attained and the load condition acting onthe binding is terminated, the release position being maintained by thenormal bias force of the single coil spring.

23 Claims, 13 Drawing Figures PATENTEUFEB22 I972 SHEET 1 [IF 3 INVENTOR.BERNARD E. BERLENBACH ATTORNEY PATENTEDFEBZZ I972 3, 643,977

INVENTOR. BERNARD E. BERLENBACH ATTORNEY SKI BOOT HEEL BINDINGINTRODUCTION This invention relates to a safety heel binding and moreparticularly to a heel binding of the type having an elongated bodymember having a forwardly positioned heel holding means swingablerelative to a base member about a rearward horizontal pivot axisperpendicular to the axis of the ski runner but parallel to the top faceof the runner. In that way, the heel-holding means is pivoted from aholding position in which the heel holding means is substantiallyabutting the top face of the runner, to a release position in which theheel-holding means is raised from and inclined to the top face of therunner.

BACKGROUND OF THE INVENTION Heel bindings of the type described, aredesigned to swing about the rear positioned pivot axis in response toupward forces acting on the skiers boot to releasein a controllablemannerthe boot heel from the binding. To provide a sufficiently widerelease arc in the full release position, heretofore heel bindings havebeen characterized by multijointed cooperative lever elements havinglong spaced-apart pivot axes, such as shown in U.S. Pat. Nos. 2,823,922,entitled Safety Binding For A Ski, Bernard E. Berlenbach, issued Feb.18, 1955, and 3,175,349 entitled Safety Heel Ski Binding," G. Schweizerissued Mar. I7, 1964. Not only are such bindings rather cumbersome inoperation, they also may be difficult to maintain due to theaccumulation of water, dust and grime at the small force accepting pivotareas of the levers. They also may have the following additionalproblems:

1. inaccuracy in release, especially where a combination of springs areused, much as a coil spring in combination with a leaf spring;

2. lack of vertical, angular play in the binding about its rear pivotaxis prior to full release in direct proportion to an initially highangular rotation per low load conditions followed by low angularrotation per high load conditions until release of the heel from thebinding;

3. use of spring combinations which under accident release conditions,in a matter of speaking, fight rather than aid in the release of theboot from the binding since, usually, the springs of such bindings exerta force which always tends to act in the direction tending to maintainthe boot on the ski runner;

4. lack ofa properly engineered binding in which considerable time andbending acrobatics are required for the skier to effect detachment ofthe binding from the boot; although some prior heel bindings have beenprovided with release spurs, such spurs must be positioned at therearward portion of the binding in order to have sufficient mechanicalleverage to effect opening of the binding.

OBJECT OF THE INVENTION Although the objects of the invention areimplicit from the foregoing, it is a particular object of the presentinvention to provide a compact, low cost, yet easily maintained ski bootheel safety binding of the type described, for controllably anchoringthe heel of the boot to a ski runner, the binding being releasable inresponse to upwardly directed forces thereto and having the followingfeatures, singly or in combination:

i. a single coil spring which under manual or accident operatingconditions, after the operational release level of the binding isexceeded, does not fight the release of the ski boot relative to therunner, but in fact aids such release and, cooperates in the maintenanceof the binding in the full release condition after external loadconditions acting on the binding, are terminated;

ii. freedom of vertical play for normal skiing operations;

iii. capacity to provide complete release over a rather wide release aremeasured with respect to the rear pivot axis of the binding;

iv. accurate and crisp release characteristics when a preselectedoperational release level is exceeded; and

v. flexible operations such as having the capacity to be manually openedby slight pressure as by using the tip of a ski pole without bendingacrobatics or direct manual manipulation of the binding combined withthe capacity to be automatically opened only when abnormal external legstress conditions occur.

SUMMARY OF THE INVENTION In a heel binding of the type having elongatedbody member having a forward heel boot holding means, a body memberswingable relative to a base member about a rearward horizontal pivotaxis substantially perpendicular to the axis of the ski runnersubstantially parallel to the top face of the runner, whereby the heelboot holding means is pivoted from a holding position in which the heelholding means is substantially abutting the top face of the runner, to arelease position in which this heel holding means is raised from andinclined relative to the top face of the runner, the improvementincluding:

a. a single coil spring carried by one of the body members and the basemember operating along a zone of action;

b. a V-frame connecting means positioned intermediate the rearward pivotaxis of the binding and the heel-holding means in operative contact withthe single coil spring, and including first and second leg meanscarrying cooperative broad-contacting, complementary surface means attheir swingably engaging surfaces to each other, one of the leg meansalso carrying thereto a substantially disconnectably connecting L-shaped cam surface aligned with the zone of action of the spring;

c. linking means for connecting the first and second leg means to thebody member and the base member, respectively, a pair of horizontalpivot axes, and including a stationary pin means disconnectablypositioned with respect to the disconnectably connecting L-shaped camsurface on the one leg means to normally prevent pivotal tilting of thebody member relative to the base member, but being adapted to releasefrom said cam surface allowing relative angular displacement of thefirst and second leg means when subjected to either of two loadconditions corresponding to (i) an accident condition or (ii) a manualrelease condition above the operational release level of the binding;

d. single coil spring adapted to undergo axial movement to release thestationary pin means of said linking means from the disconnectablyconnecting cam surface carried on the one leg means, by cooperativeangular movement of said leg means in response to a load conditionresolvable into an antibias component force acting along the zone ofaction opposite to the normal bias force of the single coil spring;

e. after release of the stationary pin means of the linking means fromthe cam surface, continued depthwise displacement of the horizontalpivot axis being aided, at least in part, by the normal bias force ofthe single coil spring until the release position of the heel-holdingmeans is achieved, after the release position is attained and the loadcondition acting on the binding is terminated, the release positionbeing maintained by the normal bias force ofthe single coil spring.

In accordance with the present invention, the body member is furthercharacterized by the provision of a vertical bore fitted with plungermeans, said vertical bore being at a position along the body memberadjacent to said boot holding means forward of the horizontal pivot axisof the binding so that when the plunger means is actuated, as undermanual load operating conditionssuch as by manipulation of a ski poletocontact, after downward movement, the remote end of one of the leg meansof the V-frame connecting means to cause rotation thereof, the rotationin turn causing corresponding directional rotation of the other legmeans whereby disengagement of said linking means from the cam surfaceof the other leg means can be achieved.

In accordance with a principal embodiment of the present invention, thelinking means for attaching the first and second leg means to the bodymember and the base member and to each other, comprises at least astationary pin means and a pair of movable pin means. One of the movablepin means adapted to define, in cross section, an arcuate travel path assaid binding moves from its holding to its release position having acenter of formation coincident with the rear pivot axis of the binding;the other movable pin means adapted to defined, in cross section, acomplex arcuate pathway having a first travel segment having a center offormation coincident with the stationary pin means and a secondary saidtravel segment having a center formation coincident with the rear pivotaxis of the binding. Accordingly, the complex arcuate path of the othermovable connecting pins resembles the letter S in cross section.

Thus, during the relative angular movement of the leg means, thedirection of angular movement of one of the leg means with respect toits horizontal pivot axis, reverses and undergoes opposite angularmovement immediately after the stationary pin means is released fromdisengagement with the cam surface carried on the other leg means, thereversing angular movement aided in part by the biasing force of thesingle coil means.

Under all load conditions, the stationary pin means is fixed a constantdistance with respect to the top face of the ski runner. Under accidentconditions, as the first and second leg means of the V-frame connectingmeans rotates with respect to said stationary pin means, tangentialcontact between the stationary pin means and the cam surface ofthelinkage means can vary not only with load but also with angle ofinclination of the cam surface from horizontal since the cam surfaceitself is undergoing rotation. Under load conditions associated with themanual release condition, the amount of angular rotation of the legmeans relative to one another is dependent only upon the magnitude ofthe load condition. Accordingly, use of a dual response binding allowsrelease of the stationary pin means relative to the cam surface undertwo distinct load conditions: a rather high operational release levelinvolving accident load conditions and, a rather low threshold releaselevel involving a manual release condition.

In accordance with another aspect of the present invention, stationaryfirst pin means can be associated, depthwise, with a given elevationabove the cam surface, at least in the holding position of the binding.Thus, initial movement of the leg means prior to tangential contactbetween the cam surface and the stationary pin means is directly independence upon the magnitude of the load condition acting on thebinding irrespective of whether that load condition is associated with aaccident or manual release condition. That way the skier, as during adownhill descent, can have a feeling of the release condition-strong orweakof his binding.

In accordance with another aspect of the present invention, the linkingmeans includes arcuate wall means in particular positionalrelationship-angularwisewith the stationary pin means so as to allowrelative rectalinear movement therebetween. Preferably, the arcuate wallmeans is integrally formed as a slot within one of the leg means incapture relationship about the stationary pin means. However, only whena particular angular position has been achieved by said one leg means,does the slot become aligned so that relative movement between the slotand stationary pin means can occur. As depthwise displacement of thehorizontal pivot axes occurs, aided in part by the bias force of thesingle coil spring, there is thus created a rather wide, release are forthe binding even though relative angular rotation of the leg means withrespect to the stationary pin means has been terminated, and even thoughthe first and second horizontal pivot axes of the linkage means areclosely spaced relative to one another.

In another aspect, the arcuate wall means is not formed within said oneleg means but comprises a pair of matched arcuate slots formed in a pairof support members attached opposite on side walls of the base member incapturing relationship about the stationary pin means. The matchedarcuate slots are adapted to allow angular rotation of the V-frameconnecting means about a semistationary pin to define a first travelpathway but then allow the semistationary pin to rectalinear travelalong the slots to define a second arcuate pathway.

In accordance with another aspect of the present invention, thecomplimentary operative surface means at the engaging surface of thefirst and second leg means is further characterized by wall meansforming a central cavity having at least a curved end wall formed on oneof the leg means and a bulbous surface on the other of said leg meansadapted to broadly contact the curved end wall. The surfacecomplimentary operative means is adapted to interchange forceinitiating-force follower functions in dependence upon the direction ofrelative angular movement of the one leg means relative to the other,i.e., as the one leg means undergoes reversal of angular rotation withrespect to its pivot axis, so does the force initiatingfollowerfunctions of said complimentary operative surface means. Further, thecomplimentary operative surface means also form a stabilizing base fortransfer of motion from either one of the leg means to the other underload conditions either produced and corresponding to an accident ormanual release condition. Such stable linking of forces can occurirrespective of the fact that dirt and grime may be caked on portions ofthe adjacent surfaces.

In accordance with another aspect of the present invention, pivotterminating means is carried on at least one of the leg means forterminating simultaneous rotation of the leg means with respect to thestationary pin means. The termination occurs, in cross section, prior tohaving the three pin means comprising the linking means pass into anovercenter, togglelocking condition.

In accordance with another aspect of the present invention, an improvedheel holding means carried at the forward end on the body membercomprises:

i. a ruggedly constructed flange projection fixedly attached to the bodymember having a top surface adapted to form a floor for the heel of theski boot and ii. a less ruggedly constructed laterally flared bridgingmeans attached by pivot allowing connecting means at the forwardterminus of the flange projection. The bridging means has a top surfacehorizontally aligned, in the holding position of the binding, with thetop face of the fixed flange projection, at least in the vicinity of theconnecting means, but, is positioned in a slightly inclined orientationover its remaining length with respect to said ski runner. As thebinding of the body member tilts about the rear axis to achieve a moreinclined position with respect to the ski runner, the connecting meansis adapted to allow the bridging means to oppositely pivot, by gravity,about a horizontal axis parallel to the rear pivot axis of the binding.In that way, the top face of the support projection becomes more exposedas the bridging means pivots away to a more inclined position wherebywhen external forces are applied at the boot holding means, as when theskier steps into the bindings to reconnect his boots to the runners, theentire load can be directly applicable to the more rugged flangeprojection.

In accordance with another aspect of the present invention, the singlecoil spring is attached within an almost horizontal inclined bore formedwithin the body member, and is provided with a spring biasing meansmovably attached within the bore in contact therewith adapted to adjustthe operational release level of the binding. Included therewith isindicating means carried on the spring biasing support means having anindexing pointer exposed to and visible at the exterior of the bodymember, to indicate the operational release level generated by thespring biasing support means.

DESCRIPTION OF DRAWINGS In order to have a clear understanding of theinvention and the manner in which it is carried out, reference is nowmade to the accompanying drawings in which:

FIG. 1 is a perspective exploded view of the ski binding of the presentinvention positioned upon the ski runner for release of the heel of theski boot in an upward direction with respect to the top face of therunner;

FIG. 2 is a side elevation, partially cut away, of the body member ofthe ski binding of FIG. 1 illustrating, in detail, the V-frameconnecting means which allows control pivoting of the body memberrelative to the stationary base member about a rear pivot axisperpendicular to the axis symmetry of the ski runner but parallel to thetop face of the runner;

FIGS. 3a-3d are partial fragment views of the V-frame connecting meansof FIG. 2 in various pivoting positions as the body member pivotsrelative to the. base member;

FIG. 4 is an exploded view of the V-frame connecting means of FIGS.3a-3d illustrating the constructional details of one leg membercomprising a three-elemented structure while the other leg means isillustrated as comprising a two-elemented structure;

FIG. 5 is a side elevation of the two-elemented leg means of FIG. 4;

FIG. 6 is a side elevation of a new embodiment of the twoelemented legmeans of FIG. 4 having integrally formed pin means attached nearitscenter of gravity;

FIG. 6a illustrated, in more detail, the pin means of the alternatelinkage element of FIG. 6;

FIG. 7 illustrates a side elevation of one of a pair of support memberswhich connect to the alternate two-elemented linkage member of FIG. 6;

FIG.7a is a section along the line 7A-7A ofFIG. 7 and;

FIG. 8 is a side elcvation-ofa V-frame connecting means of FIG. 2 in itsfull release position.

DESCRIPTION OF PREFERRED EMBODIMENTS Reference is now made to thedrawings. FIG. 1 illustrates an embodiment of the present inventiondepicting a ski binding 10 adapted to disconnectably connect a ski boot(not shown) relative to a ski runner (also not shown) and comprises abase member 11 adapted to be fixedly connected to the top face of theski runner and a body member 12 carrying, at its forward end, aboot-holding means 13. Body member 12 is pivotedly connected to basemember 11 at a rear end, as by pivot pin 14. Such attachment permitspivoting of the body member 12 about the pin 14 to release a ski bootfrom the ski runner, i.e., to release the ski boot from a holdingposition in which the boot holding means 13 is adjacent to the top faceof the ski runner to the release position in which the boot holdingmeans 13 is elevated from the runner. In order to become betteracquainted with the binding of the present invention under all operativeconditions associated with the controlled release of the ski bootrelative to the ski runner, a description, in sequence, of theaforementioned elementsbase member 11, boot-holding means 13, and bodymember 12is set forth below.

BASE MEMBER 11 Slide bar 15 of base member 11 is seen in FIG. 1 toinclude a planer base 17 fitted with upright projections 19a and 19b atits forward end, provided with horizontal bores 20 to accommodate pivotpin 21. Rearwardly located on planer base 17 are upright projections 22aand 22b. Horizontal bores 23 are there provided to accommodate the pivotpin 14 parallel to pivot pin 21. The forwardly positioned projections19a and 19b attach, by pin 21, the slide bar 15 to one end of V-frameconnecting means generally indicated at 24 within a cavity 25 of bodymember 12. The manner of attachment is described hereinafter. At a moreelevated extremity, the V-frame connecting means 24'is connected to thebody member 12 by pivot pin 18. The purpose of V-frame connecting means24 is to effect controlled release of the body member 12 with respect tobase member 11 so as to permit rotation-tilting of the body member 12about pivot pin 14. It is evident that control characteristics of thebinding are enhanced by the fact that the cavity 25 of the body member12 is closed on five sides by the walls of the cavity and on the sixthside by the base member 11, at least in the holding position, so as toprevent easy intrusion of dirt, snow, grime in interior of the bodymember.

Side bar 15 is not to be firmly mountedlengthwisewith respect to the skirunner, but is arranged to slide rectilinearly therealong usingstationary track 16 as a guidcway. As indicated, stationary track 16 isprovided with C-shaped upright sidewalls 26 properly dimensioned in thelateral direction to slidably engage the sides of slide bar 15.Horizontal movement of the slide bar 15 along track 16 is provided bycontrolled rotation of plug 27 at the rearward end of the bar [5. Plug27 is provided with threads which extend through central opening 28 inthe planer base 17, into contact with rack 29 of track 16. Opposite thethreads, the plug 27 is formed with a recessed head27a movablyattachable within an opening (not shown) in end wall 22c of slide bar15, attachment being by means of coil spring 30 in conjunction withretaining rod 31. Specifically, coil spring 30 is arranged to bepositioned between the plug 27 and upward extending tab 34 at theforward terminus of opening 28 on planer base 17 in symmetrical positionabout guide rod 31. Since the threads of plug 27 engage rack 29 of track16, rotation of the plug 27 is directly translated into rectilineartravel of the slide bar 15 along track 16. The track 16 can be affixed,semipermanently to the ski runner, using fasteners such as wood screws35 extendable through openings 36.

It is evident that movement of the slide bar 15 with respect tostationary track 16 also carries the body member 12 and boot holdingmeans 13 in corresponding rectilinear travel along the ski runner. Sincethe toe bindings attachable to the ski runner remain fixed during suchmovement, ski boots of different sizes can be easily accommodated.

BOOT-HOLDING MEANS 13 Boot holding means 13 is seen in FIG. I to includea bootretaining plate 37 having a forwardly extending upper arcuatecleat 38 adapted to fit in registration on the upper projection of theboot heel. Cleat 38 is supported by support block 39. The forward faceof the support block 39 is curved to form a cavity, or pocket, belowcleat 38 for accommodating the more bulbous portion of the boot heel.

In order to allow necessary vertical adjustment (so as to accommodateski boots of different sole thickness) of the cleat 38 (and block 39)with respect to fixed flange projection 40 at the forward face of thebody member 12, the block 39 is provided with side rails 41. Duringassembly, rails 41 are placed in mating engagement with verticallyextending shoulders 42 on the forward face of the body member 12. Therails 41 and shoulders 42 have oppositely diverging vertical sidewallswhich prevent their disengagement due to the action of horizontal forcesacting on the binding, but allow vertical displacement therebetween. Inorder to control the vertical displacement of the cleat 38 relative tothe flange projection 40 of the body member 12, the block 39 is alsoprovided with a central fitted rack 43. Rack 43 is preferably parallelto rails 41. During assembly plug 44 is positioned within divided cavity45 at the forward face of the body member 12 in threadable engagementwith rack 43. As plug 44 is rotated, the cleat 38 and block 39 arecaused to travel vertically with respect to the projection 40.Accommodation of any size depthwise of heel boot sole between cleat 38and projection 40 is thus assured.

Since projection 40 may not be as wide in the lateral direction as theboot heel, a less rugged, but wider bridging support 46 is seen to bepivotedly attachable to the forward extending face of the projection 40as by the accommodation of pivot pin 47 within aligned bores 48 and 49of the bridging support 46 and the projection 40, respectively. Theprojection 40 is also provided at side surfaces with shoulders 51dimensionally spaced with respect to bore 49 of the projection 40. Afterassembly, shoulders 51 form a stop to terminate pivotal rotation(clockwise, as viewed) of the bridging support 46 about pin 47.Specifically, upright surfaces 53 of tabs 52 make contact with theshoulders 51 after a selected degree of angular rotation has occurred.

It is evident from FIG. 1 that flange projection 40 is preferablyconstructed integrally with the forward face of the body member 12. Andit should be of sufficient rugged design to withstand, withoutmechanical breakage, the impact of normal operating forces incident onprojection 40, as might be generated by the heel of the ski boot as theskier steps into his bindings. On the other hand, the bridging support46 is of less rugged construction than projection 40. As indicated, thebridging support 46 includes a top wall 54 reduced in thickness overthat of projection 40, but has downwardly extending sidewalls 55 at itsside and forward edges. In the lateral direction, the width of thebridging support 46 is seen to be greater than that of track 16. Thus,in the holding position of the binding such as indicated in FIG. 2, thebridging support 46 can assume an inclined position with respect to topface 60 of the ski runner 61 to comfortably accommodate the heel of skiboot 62. Further, as indicated in FIG. 2, in the vicinity of pivot pin47, the bridging support 46 is alignedhorizontally-with the uppersurface of flange projection 40. However, when the binding is in theopen-releaseposition as indicated in FIG. 8, the bridging support 46 isseen to have been pivoted, by gravity, from the inclined positiondepicted in FIG. 2 through a selected arcuate angle a determined by theslope of the shoulders 51 with respect to surfaces 53 of tabs 52 (FIG.1). In that way, forward extremity 63 of projection 40 seems to beexposed so as to accept the usual operating forces generated by a skiersboot as he places his boot into the binding. As previously indicated,projection 40 is capable of accepting such operating load conditionswithout mechanical breakage because of its rugged design; the lessruggedly constructed bridging support 46 is of course, removed fromexposure to such load conditions.

BODY MEMBER 12 Body member 12 is seen in FIG. 1 to be of an elongatedconstruction. As previously mentioned, at its forward end is locatedboot-holding means 13. At its rearward end, there is positioned a plug65 in threadable compression with a single coil spring 66. In operation,the plug 65 varies the urging force of the coil spring 66 relative tothe V-frame connecting means 24. Specifically, by rotation of the plug65, forward end 67 is moved relative to the oppositely positionedcaptured end of the spring 66. In that way, the active coil length ofthe spring can be varied so as to vary the operation threshold releaselevel of the binding. Of course, the relative magnitude of theoperational threshold release level of the binding must be viewable bythe skier in his upright skiing positions, For this purpose, guidepointer 68 is fixed in elevation within the body member 12 in contactwith the threads of the plug 65, and is allowed to travel rectilinearlyin response to rotation of plug 65. Indexing scale 69 is fixedlypositioned above the travel of the pointer 68 to allow the skier toobserve as through vertical slot 70, the position of the pointer 68relative to the scale 69. Guide pin 71 fitted within a bore at the endsof the slot 70 guide and support the pointer 68 during travel.

The term operational threshold release level" of the binding refers tothe magnitude of the urging force usually of a relatively high magnitudecreated by compression of the single coil spring 66 as by rotation ofplug 65, so that force being used to resist extra upwardly directedforces acting on the binding as the skier tumbles from an uprightposition during a skiing accident. However, the present invention alsocontemplates release of the binding in an manual condition at a loadcondition of much lower magnitude, in the usual case, than that requiredto release the binding in an accident condition. Specifically, suchrelease can be achieved by plunger 72 being downwardly depressedrelative to vertical bore 73 as by use ofa tip ofa ski pole.

Operation of the V-frame connecting means 24 to achieve release of thebinding under manual or accident conditions will now be described withreference to FIG. 2.

V-FRAME CONNECTING MEANS 24 Reference is now made to FIG. 2. Aspreviously mentioned,

V-frame connecting means 24 is positioned within central cavity 25 ofthe body member 12. As indicated in FIG. 2, it includes (i) firstupright elongated leg means linkably attached to the body member 12 bythe pivot pin 18, the leg means 80 carrying an L-shaped cam surfacemeans 82 at its forward end, and (ii) second bulbous leg means 81swingably and linkably connected to the first leg means 80 by pivot pin84 and to the base member 11 by the previously mentioned pivot pin 21.Second leg means 81 is also provided with a slot 85 over its centralportion. (In the present invention, the pivot pins 18, 21 and 84, aswell as slot 85, aid in linking the first and second leg means 80, 81relative to the body member 12 and base member 11 respectively as wellas to each other. For these reasons, the function of these elements,collectively, can be referenced by the term linking means") In thenormal holding position, depicted in FIG. 2, the coil spring 66 isoperatively placed in contact with rear boss 87 at the rear surface ofthe first leg means 80, the operational threshold release level of thebinding under accident conditions being determined, as previouslymentioned, by the relative position of the plug 65 along bore 89. Thegenerated spring bias force acts on the first leg means 80 at point 88.The bias force, in turn, is transferred via vertical cam surface 820 tostationary pivot pin 21 to also establish a minimum actuation level ofthe binding. In this regard, note that cam surface 82a is horizontal inFIG. 3a and is spaced, in elevation, a depth distance D from thestationary pivot pin 21. When external forces act on the binding abovethe minimum actuating level of the binding usually of a relatively lowmagnitude the body member 12 can undergo slight tilting above pivot pin14. This causes coil spring 66 to undergo compressional axial movementto change the operating state of spring 66. Assuming that the externalforces are above the progressively increasing responsive curve for thespring 66, the rate of change of curve can be relatively low during thisphase of binding operation, i.e., high spring deflection per unit ofexternal force applied. However, when cam surface 82b comes intotangential contact with the pivot pin 21, defining an intermediatethreshold level, then progressively greater increasing magnitudes ofexternal forces are required to continue the tilting of the body member12 about the pivot pin 14 at least in the accident condition. Spring 66is adapted to abruptly change at the intermediate threshold level as thecam surface 821: is placed in tangential contact with the stationarypivot pin 21. Equivalencywise, the operation of the binding between theminimum actuation and the intermediate threshold levels is initiallygoverned by the response characteristics of spring 66 unaffected by theangle of inclination of the cam surface 82h as the cam surface 82!;travels the depth distance to contact the pivot pin 21 but, when camsurface 82b contacts pin 2], response characteristics of the spring aremodified by the aforementioned angle of inclination to define a stiffer"response curve, i.e., lower spring deflections per unit of externalforce applied, terminating in the generational threshold level, or fullrelease condition for the binding. However, because the external forcesacting on the binding are above the minimum actuation or intermediatethreshold levels does not mean the operational threshold release levelwill be achieved. But, in fact, such forces may disappear as conditionsare corrected before the binding achieves its full release position. Inany event, vertical play of the binding, i,e., travel along the verticaldistance, produces a response condition indicative to the skier of therelease characteristics of his bindingeither strong or weak-which isdeemed to be valuable to all skiers. If the external forces acting onthe binding are above the operational threshold level of the binding,however, the horizontal cam surface 82b will aid, ultimately, in thecomplete release of the binding, as explained below.

Consideration will now be given to the description of bulbous second legmeans 81. As indicated in FIG. 2, the bulbous second leg 81 has aprojection 86 at its free end which, in the holding position of thebinding is positioned directly below bore 73 in alignment with theplunger 72. Accordingly, manual manipulation of the plunger to travel onbore 73 places it in contact with free projection 86 of the second leg81 to also cause release of the binding, but using external forces whichare substantially below that usually occuring in the accident condition,as explained below.

RELEASE OF THE BINDING Attention is now directed to the general natureof the initiation of release operation of the binding As previouslymentioned, release of the binding is in response to one or two loadconditions: (i) an accident load condition (which can be a relativelyhigh amplitude, initiated by upward components of external force actingthrough the ski boot 62 onto the body member 12 which, in turn, act uponfirst elongated leg means 80 through pivot pin 21, and (ii) a loadcondition caused by manual depression of the plunger 72 in a downwardmove- I ment to contact projection 86 of the second bulbous leg means81. Pivotal linking of the leg means 80 and 81 relative to the bodymember 12, base member 11, respectively and to each other, is by meansof stationary pin 21, movable pins 18 and 84, as well as slot 85. Undereither load condition, however, note that the stationary pivot pin 21 islocated within the zone of action of the single coil spring 66 andperforms, during the initial stages of release, a latching functionpreventing full rotation of the leg means 80, 81 Thus, components of theexternal load established at pin 21 can be seen to be rotatable intocomponents aiding along the zone of action of the spring 66 but oppositein direction to direction of its normal bias force. Movable pivot pin 84is also closely positioned to the aforementioned zone of action of thespring 66. However, the load actuation points acting on the leg means 80and 81 are seen to be more remotely spaced from the zone of action ofthe spring 66. Accordingly, mechanical leverage under either loadcondition can still be achieved without resort to use of long lever armsand pivot axes.

The actual operation of V-frame connecting means 24 is of a complexednature, being for example in dependence upon the nature of the forceinitiating release of the binding. For convenience of description, a keyto understanding the nature and features of the V-frame connecting means24 is to follow, during release, the imaginary arcuate pathways oftravel traced by the movable pins 18 and 84. These arcuate pathways aredepicted in FIG. 2 at reference numbers 90 and 91, path 91 resembling an8" in section.

As indicated, pathway 90 defines, in cross section, the arcuate travelpathway of pin 18 from its holding position (FIG. 2)

to its release position (FIG. 8). It is evident that pathway 90 has acenter of formation concomitant with and coincident with the rear pivotpin 14. Note also that the angular direction of pathway 90 is constant.However, for the pathway 91, indicative of the travel of pin 84, a morecomplexed pathway has been traced. As indicated, a first segment 910 hasa center of formation coincident with stationary connecting pin 21.While a second segment, 91b, has a center of formation concomitant withrear pivot pin 14. Pins 18, 84 begin travel along the pathways 90 and 91corresponding to relative arcuate rotation of the leg means 80 and 81when external forces above at least the minimum actuation level, act onthe binding.

It is evident that during travel of pins 18, 84 along pathways 90,91,the first and second leg means 80, 81, undergo angular rotation withrespect to each other, to wit: from a tight V-position imaginary linesthrough pins 18, 21 and 84 establishing a V-orientation, (FIG. 3a)through an intermediate wide, V- position (FIG. to finally a fullrelease position, slotted V- position (FIG. 3d). During such rotation,pins 18 and 21 are seen to undergo increasing depthwise displacementwith respect to each other.

FIG. 3a illustrates the manner in which the stationary pin 21 ispositioned, in elevation, with respect to the L-shaped cam surface means82. In detail, FIG. 3a illustrates the binding prior to the occurrenceof manual actuation forces by depression of plunger 72 and causingrotation of the bulbous second leg means 81.

As shown, the projection 19a of base member 11 extend upwardly intocavity 25 of the body member 12 to accommodate, in elevation, thestationary pin 21 parallel to pin 18. As indicated, pin 21 is fixed, inelevation, above the top face of base member 11, a constant distance Land, as previously mentioned above horizontal cam surface 82b, adistance Although the fact that the stationary pin 21 is not intangential contact with the horizontal flat surface 82b does not preventthe establishment of a minimum actuation level for the binding throughits contact with vertical cam surface 820, such level defining minimumactuation level of the binding which must be overcome by resolvableexternal forces acting opposite thereto before there can be upwardrotation of the body member 12 with respect to base member 11.

Load conditions which allow for and cause movement of pins 18, 84 withrespect to stationary pin 21 are initiated at the remote ends of thefirst and second leg means and 81 in the manner previously described.Specifically, a high-load condition acting at pin 18 and, a usuallylower load condition acting at the free projection 86 of bulbous legmeans 81. In either condition, leverage position is created: (i) in theaccident condition, the distance between pins 18 and 21 serves as thelever arm, with the component of resolved external force being appliedat pin 21 along the zone of action ofspring 66; and (ii) in the manualcondition, the pin 21 serves as the leverage apex, with the movement dueto the external force applied at projection 86 of leg means 81multiplied by the distance between projection 86 ofleg means 81 and pin21 being equal to an opposite but equal movement generated by compositeforces at the intersection of complimentary operative surface means 93(carried on the leg means 80,81) and the zone of action of the coilspring 66 multiplied by the distance between the pin 21 and the zone ofaction of the spring. Since the leverage position of pin 21 relative tothe forces applied to leg means 81, is not equal therebetween, it isevident that the composite force will be greater than the external forceapplied to projection 86. Accordingly, in the manual release condition,even low forces applied at projection 86 can initiate release ofthebinding. Depthwise distance between the movable pins 18 and 84 is fixedthroughout operations of the binding. As movement of either pin 18 or 84occurs, as due to either one of the two previously mentioned loadconditions above the minimum actuation level of the binding, the firstleg means 80 is caused to rotate in a clockwise direction against coilspring 66 to cause compressional movement thereof until the operationalrelease level is achieved.

It is evident in this regard that between the first and second means 80and 81, reactive forces transferred therebetween are aided bycomplementary operative surface means 93 formed between the leg means 80and 81. Complementary operative surface means 93 are seen in FIG. 3a tobe centralized about the zone of action of the coil spring 66. When thestationary pin 21 reaches thd outer terminus 820 of the cam surface 82!)as shown in FIG 3b, however, the leg means 80, 81 are released for fullangular rotation, since the forces that had previously acted on the coilspring 66 and caused compressional axial movement thereof in a directionopposite to normal bias force of the spring are released. Thereafter,the spring 66 undergoes opposite axial movement, in the direction of itsbias force, continued rotation of the first and second leg means 80, 81thus being aided in part, by the normal biasing force of the spring 66,unoppossed by the external load conditions.

FIG. 3b is the side elevation depicting release of cam surface 82b fromstationary pivot pin 21. As previously indicated, prior to release, thefirst and second leg means 80, 81 rotate in a clockwise direction aboutpins 18, 21, respectively, causing axial compressional movement of thecoil spring 66 and carrying the pin 84 along imaginary first pathwaysegment 91a, whose center formation is coincident with stationary pivotpin 21. Thus, an imaginary plane C C through the movable pins 18 and 84is seen to be shifted from a vertical location (FIG. 3a) to a newoblique position (FIG. 3b) identified by the acute angle correspondingto the change in action coil length of the coil spring. Likewise, thepoint of tangential contact 94 between the stationary pivot pin 21 andthe cam surface 82b has shifted from a vertical location to a likeangular orientation. Accordingly, when the binding is subjected to highstress external load conditions at pin 18, as would occur during anaccident condition, it is evident that the load condition acting attangential contact point 94 to cause counterrotation of the first legmeans 8-and axial compressional movement spring 66-and ultimatelyrelease the cam surface 82b therefromis a function of both the magnitudeof the load condition at point 94 as well as the angle of inclination ofthe cam surface 82b from vertical. Prior to the cam surface 82b beingplaced in with the stationary pivot pin 21, i.e., intermediate thresholdlevel, the fact that the stationary pivot pin 21 is positioned avertical distance D above the cam surface 82b allows for generation ofthe initial angle of inclination depicted in FIG. 327. Accordingly, theurging force of the coil spring 66 creating the minimum activation levelof the binding up to the intermediate threshold level (when the pin 21contacts cam surface 82b) can be relatively-on an absolute scale-low. Aspreviously mentioned, in the accident condition, after the cam surface82b contacts the pivot pin 21, the resolved components of force causingimpression of spring 66, are a function of the angle of inclination B ofthe cam surface 82b from vertical. Thus, the absolute magnitude of theexternal forces-in the accident conditionacting on the binding may benecessarily required to be quite high to achieve the threshold releaselevel of the binding. Assuming the external forces are above that level,full rotation of the second leg means 81 about stationary pivot pin 21always ensues.

On the other hand, in the manual release condition indicated in FIG. 3b,plunger 72, after being placed in motion, contacts the remote projection86 of the second leg means 81 to cause rotation thereof about pivot pin21. In turn, rotation of the first leg means 80 about pin 18 ensues inthe manner of a teeter-totter" with pin 21 serving as the leverage apexin the manner previously described to release cam surface 82b from thestationary pin 21. Accordingly, the external load condition applied tothe remote projection 86 is seen to produce angular movement of thefirst and second leg means against the bias force of the spring coil 66,independent of any angle ofinclination existing at the cam surface 82b.

FIG. 30 is another side elevation of the first and second leg means 80,81 depicting termination of the relative angular rotation thereof afterrelease of the cam surface 82b from the stationary pivot pin 21. Duringsuch angular travel, movable connecting pins 18 and 84 trace differentinstantaneous positions along imaginary paths 90 and 91, respectively.Specifically, pin 84 traces path segment 91a, while pin 18 traces pathsegment 90a.

Attention is now directed to the structure of bulbous leg means 81 forterminating relative angular rotatiop between the leg means 80, 81. Asindicated in FIG. 30, bulbous leg means 81 is seen to be provided with apivot terminating means 95, such as a flanged shoulder, aligned withcomplementary surface means 93. After release of the cam surface 82bfrom contact with stationary pin 21, rotation of the leg means 80, 81are aided by the spring coil 66, as previously mentioned, untilterminated by the shoulder 95 contacting undersurface 96 of the firstleg means 80. Additional external forces may be applied to the bindingat this time (other than by coil spring 66) to effect release, e.g., theskier may apply upward pressure through the heel of his ski boot.

Termination of the relative pivotal motion between the first and secondleg means 80, 81, however, does not terminate relative angular movementof the binding. As indicated in FIG. 3d, tilting the body 12 relative tobase 11 continues after the shoulder 95 of bulbous leg means 81 contactsthe undersurface 96 of the leg means 80 by the fact that slot 85 hasbeen angularly aligned with stationary pivot pin 21 to permit relativerectilinear travel therebetween. As indicated, the first and second legmeans 80 and 81 have thus been moved upward,

i.e., depthwise displaced. Specially, movable pin 84 has moved alongsecond segment 91b of the imaginary travel path 91; while pin 18 hasmoved along segment of imaginary path 90. With respect to the pivot pin84, it should be noted that the center formation of the second segment91b is coincident with the rear pivot axis of the binding, i.e., pivotpin 14 of FIG. 30, and is thus coincident with the center of formationgenerated by the travel of pivot pin 18. In this regard, movable pin 84connecting the leg means 80 and 81 together, does not pass through aplane coincident with stationary pin 21 and movable pin 18, i.e., doesnot pass into an overcenter toggle locking condition. Thus, the skiercan easily connect his ski boot relative to the runner after releaseassuming the binding is in the position depicted in FIG. 3d, by simplystepping down with his boot into the binding. I

In its final full open release position, the biding has achieved awide-arc release angle without the use of long lever arms having widelyspaced pivot axes. Further, even after external force load conditionshave been removed relative to the binding, the normal biasing force ofcoil spring 66 is still operative to keep the binding in full openrelease position depicted in FIG. 8.

FIG. 4 illustrates first and second leg means 80, 81 in more detail. Asindicated, the fist leg means 80 can be ofa multielemented construction,including a pair of spaced-apart sears 97, 98 sandwiehing a centralspacer 99 therebetween. Sears 97, 98 and central spacer 99 are providedwith bores 100 at their elevated extremities to accommodate the pivotpin 18. These bores are constructed such that when assembled together,the cam surface means formed at their forward extremities is alignedparallel to the horizontal pivot axes coincident with pins 18 and 84.

Central Spacer 99 is provided with curved end wall 101 at its forwardend, by reducing the width of the spacer between broad surfaces 102.When the sears 97, 98 are placed in contact with the spacer 99, as byusing pins 104 as guides, the curved end wall 101 forms a part ofcomplementary surface means 93 of FIG. 2. After assembly of thespacer-sear subassembly has been completed, it is evident that end walls101, broad interior surfaces 105 of the sears 97, 98 together with broadwalls 107 of spacer 99 form a cavity into which can he slidably mounteda pair of Offcenter links 108 and 109 comprising leg means 81.

Offcenter links 108 and 109 are formed such that end surfaces 110 arematched-in curvature-with end wall 101 of the spacer 99 as can be seenwhen these elements are placed in the holding position of the binding(FIG. 2). Thus, irrespective ofwhich leg means 80 or 81 is undergoinginitiating movement with respect to the other, there is sufficient areaof contact between these aforementioned surfaces to allow forcetransference one to the other without high-stress points being developedbetween these units. The direction of the force transference, of course,depends upon which of the leg means has the force of action applied toit and which of the leg means reacts, in turn, to such application.During the initial state of release of the binding in the manual releasecondition, e.g., force is applied to offcenter links 108, 109 which inturn transfer such force through surfaces 110 to end walls 101 of thespacer 99. (To be sure, a part of the load is also transferred via thepivot pin 84.) However, after the stationary pin 21 has been releasedfrom the cam surface 82b, the initiating force direction can reverse.That force in the reverse direction is applied at least in part throughthe end walls 101 to surfaces 110 of the Offcenter links 108, 109 in thecomplementary fashion previously described.

FIG. 5 is a detail of link 108 of FIG. 4. As shown, the link 108includes central slot 85 having a longitudinal axis E-E formed to allowfull relative rotation of the link with respect to the stationary pin21. Link 108 has a second axis F-F which bisects projection 86 andintersects, tangentially, the pivot pins 21 and 84. Axis 15-15 is seento define in conjunction with axis F-F the angle a identified with thefull release position of the binding (FIG. 8).

In order to provide offcenter pivotal action, the links 108 does notestablish pivot axis along the axis F-F, but to one side thereof. As thelink 108 pivots with respect to pivot pin 21, the center of gravity 112is thus positioned so as to aid in the full pivoting ofthe link.

Opposite the position of projection 86 is the bulbous end surface 110previously mentioned as comprising, in part, complementary operativesurface means 93 of FIG. 2. A arcuate segment 111 of the bulbous endsurface 110 is depicted as terminating in pivot terminating flangeshoulder 95. As-arcuate segment 111 is seen to be symmetrically locatedwith respect to pin 84, there can be no relative camming motion betweenthe contacting surfaces of the link 108 relative to the searspacersubassembly of FIG. 4 during operation of the binding. However, angularmotion can be transferred by means of the contacting broad surfaces ofthese elements in the manner previously described.

MODIFICATION FIGS. 6, 6a 7 and 7a illustrate a modification of the link108 of FIG. in which, among other things, slot 85 has been eliminated,but its equivalent operational functions have been retained.

As indicated in FIGS. 6 and 6a, modified link 108 has no central slot,but does include outwardly extending spindle 113 fixedly attached to thebroad surfaces 116 of the link 108 at a location previously occupied bythe stationary pin 21 of FIG. 2. Spindle 113 extends outwardly frombroad surfaces 116 the entire width of the binding. As depicted FIG. 6a,each terminus section 117 of spindle 113 is provided with the transverseslot or keyway 118. To connect each link 108 relative to the base member11 (in FIG. 1, pin 21 serves the aforementioned function), each terminussection 117 is rotatably attached to a bracket member 120 (FIGS. 7 and7a).

As indicated in FIG. 7', each bracket member 120 is provided with acentral arcuate slot 121 having one of its sidewalls 122 (FIG. 70)provided with an arcuately extending projection or key 123. The slot 121is constructed to have a center of formation coincident with pivot pin14 of FIG. 1 after assembly relative to base member 11. In this regard,each bracket member 120 is also provided with bores 124 to aid inattachment of the bracket member to the projections 19a and 19b of thebase member 11 (FIG. 1) as on the broad walls 125 ofthe projections 19a,19b.

After attachment of the bracket members 120 to the base member 11 ofFIG. 1, the terminus sections of the spindle 113 are located within theslots 121 of the bracket members, specifically, in the manner depictedin FIG. 7.

In operation, it is evident the modified links 108 positioned asdescribed above are retained within the slots 121 by gravity during allinitial release steps of the binding viz, release of the bindings inaccordance with FIGS. 2,3a and 312. However, during such releaseconditions, it is evident that the links 108 undergo rotation, viz,spindle 113, relative to bracket members 120 until the pivot terminatingshoulders 126 (FIG. 6) carried on link 108' contact the undersurface ofthe sear-spacer subassembly in the manner described with reference toFIG. 30. In that pivot terminating position, the slots 118 of thespindle 113 are positioned in axial alignment with keys 123 of thebracket members 120 to allow rectilinear travel therebetween in themanner depicted with reference to FIG. 3d. Emphasis should be made tothe fact that the imaginary paths 90, 91 traced by pins 18, 84,respectively, (FIG. 2), remain the same for the above modificationsonlythe operative function of pivot pin 21 (FIG. 2) has been modified:equivalencywise, instead of spindle 113 remaining stationary throughoutthe operations, the operations it is rectilinearly movable during thelast phase of operations.

While certain preferred embodiments of the invention have beendisclosed, it is understood that the invention is not limited thereof asmany variations will be readily apparent to those skilled in the art.

What is claimed is:

1. In a heel-binding of the type having forwardly extending heel-holdingmeans releasably attached to a ski boot, an elongated body memberattached to said heel holding means swingable relative to a stationarybase member adapted to be attached to a top face of a ski runner about arearward horizontal pivot axis substantially perpendicular to the axisof the ski runner but parallel to said top face of said runner, saidbody member carrying said heel holding means from a holding position inwhich said heel holding means is substantially abutting said top face ofsaid runner, to a release position in which said heel holding means israised from, and inclined with respect to said top face of said runner,the improvement comprising:

a. a single coil means carried on one of said body member and said basemember, adapted to generate a biasing force, along a selected zone ofaction;

b. a V-frame connecting means positioned intermediate said rearwardpivot axis of said body member and said heelholding means in operativebiasing contact with said single coil spring, said V-frame connectingmeans including first and second leg means carrying complimentarycooperative surface means at their swingable engaging surfaces to eachother, one of said first and second leg means including disconnectablyconnected cam surface means carried on an exterior surface opposite tosaid single coil spring but in substantial positional alignment withsaid zone of action;

c. linking means for connecting said first and second leg means to saidbody member and said base member to the first and second horizontalpivot axis, respectively, substantially parallel to said rear pivot axisof the said body member, and including pin means coincident with saidsecond horizontal pivot axis adapted to the position with respect tosaid disconnectably connecting cam surface means of said one leg meansto normally prevent pivotal tilting of said body member relative to thesaid base member about said rear pivot axis, but being adapted torelease when said binding is subjected to either one of two externalload conditions corresponding to (i) an accident condition or (ii) amanual release condition;

d. said single coil spring means acting on said V-frame connecting meansadapted to undergo axial compressing movement, in dependence upon themagnitude of one of said external load conditions applied at one or theother of said leg means to release said disconnectably connecting camsurface means from said pin means, by cooperative arcuate movement ofsaid disconnectably connected cam surface means carried on said one legmeans, said cooperative movement being in accordance with the magnitudeof antibiasing forces resolvable from load condition along said zone ofaction of said single coil spring means, said cooperative movement alsocausing relative angular displacement of said first and second leg meansrelative to one another;

e. prior to full release of said binding, said angular relativedisplacement between said first and second leg means causing increasingdepthwise displacement of said first and second horizontal pivot axes ofsaid linking means corresponding to angular tilting of said body memberrelative to said base member about said rear pivot axis; after releaseof said disconnectably connected cam surface means from said pin means,continued depthwise displacement of said horizontal pivot axis beingaided, at least in part, by said normal bias force of said single coilspring means.

2. The improvement in accordance with claim 1 with the addition of pivotterminating means carried on at least one of said leg means forterminating relative angular rotation of said first and second leg meansafter release of said pin means from operative contact .with saiddisconnectably connecting cam surface means.

3. vThe improvement in accordance with claim 2 in which said linkingmeans includes arcuate wall means in positional relationship with saidpin means and adapted to allow relative rectalinear movement betweensaid wall means and said pin means after termination of said relativeangular movement of said first and second leg means, whereby additionaldepthwise displacement of said horizontal pivot axis is achieved so asto provide a wide-release are for said boot-holding means, saidadditional depthwise displacement being aided, at least in part, by thenormal biasing force of said single coil spring means.

4. The improvement in accordance with claim 3 in which said includedarcuate wall means is an arcuate slot formed integrally within saidother leg means in capturing relationship about said pin means.

5. The improvement in accordance with claim 2 in which said includedarcuate wall means of said linking means is a pair of matched arcuateslots within support member means attached to opposite upright sidewallsof said base member between said boot-holding means and said rear pivotaxis of said binding in capturing relationship about said pin means,said pin means being fixedly attached to said other leg means, saidmatched arcuate slots adapted to allow angular rotation of said pinmeans followed by rectalinear travel of said pin means with respect tosaid matched arcuate slots.

6. The improvement of claim 1 in which said linking means includesadditional pin means substantially parallel to said first-mentioned pinmeans, said additional pin means adapted to pivotally connect said firstand second leg means to each other at said swingable engaging surfacesthereof, and under manual and accident load conditions, adapted toundergo relative angular movement about said first-mentioned pin meansin conjunction with relative angular rotation of said leg means aboutsaid first and second horizontal axes, said angular movement ofsaidadditional pin means tracing from said holding to said releasepositions, a continuous arcuate imaginary pathway which, in crosssection, resembles the letter S."

7. The improvement of claim 6 in which the direction of angular movementof one of said leg means with respect to its horizontal pivot axisreverses after said disconnectably connecting cam surface is releasedfrom said first-mentioned pin means, said reversed angular movementbeing aided, in part, by said biasing force of said single coil means.

8. The improvement of claim 6 in which said linking means includes yetanother additional pin means positioned substantially parallel to saidfirst-mentioned pin means and said addi tional pin means and coincidentwith said first horizontal pivot axis, said yet another additional pinmeans connecting said one leg means to said body member and operative toundergo angular movement defining a pathway centered at and coincidentwith said rear pivot axis.

9. The improvement of claim 8 in which, in said full release position,rotation of said additional pin means is terminated prior to passagethrough an imaginary plane connecting said first-mentioned pin means andsaid yet additional pin means, said binding being maintained in saidfull release positioned at least in part by said biasing force of saidsingle coil spring means.

10. The improvement of claim 1 in which said pin means, coincident withone of said first and second horizontal pivot axes, remains stationaryunder all load conditions of said binding at a constant elevation abovesaid top face of said ski runner.

11. The improvement of claim 10 in which, under an accident responsecondition, said cooperative arcuate movement of said disconnectablyconnected cam surface means on said one leg means changing the operativestate of said single coil spring means for release of said cam surfacefrom said stationary pin means is dependent, forcewise; on the productof the magnitude of an upward component of external force applied tosaid linking means and the instantaneous angles of inclination existingbetween said stationary pin means and said cam surface means during saidarcuate movement thereof, said upward component of external force beingresolvable into said antibiasing forces acting parallel to said zone ofaction of said single coil spring means having magnitudes above aselected operational release level for said linking means.

12. The improvement of claim 10 in which said disconnectably connectedcam surface means is L-shaped in cross section and said stationary pinmeans, in the holding position of said binding, is displaced, depthwise,a vertical distance D" from engagement with a horizontal cam surfacemeans of said cam surface means so that, in operation of said binding,small excursions of arcuate movement of said body member with respect tosaid base member, prior to engagement of said horizontal surface meanswith said stationary pin means, are allowed in dependence upon a loadcondition acting on one or the other of said leg means resolvable intosaid antibiasing forces acting parallel to said zone of action of saidcoil spring means, said resolved antibiasing forces being above at leasta selected minimum activation level of said single coil spring means.

13. The improvement of claim 12 in which, after said stationary pinmeans contacts said horizontal cam surface means of said L-shapeddisconnectable connecting cam surface means under a load conditioncorresponding to a manual release condition, continued relative angularrotation of said leg means for release of said horizontal cam surfacemeans from said stationary pin means, is dependent upon the magnitude ofthe load resolvable into said antibiasing force acting parallel to thezone of action of said coil spring means at either one or the other ofsaid leg means but independent of the angle of inclination existingbetween said stationary pin means and said disconnectable connected camsurface means, said antibiasing force resulting from a leveragecondition utilizing said stationary pin means as a leverage apex so asto easily effect release of said horizontal cam surface means from saidstationary pin means.

14. The improvement of claim 1 in which said complimentary operativesurface means carried on said first and second leg means, althoughrotatable relative to each other, is further characterized by broadcontacting, force accepting areas whereby high point stress conditionsthereon due to impingement of said antibiasing and normal biasing forcesduring operation of the binding are avoided.

15. The improvement in accordance with claim 14, in said holdingposition, in which said zone of action of said coil spring meansintersects said complimentary operative surface means in the regions ofsaid broad contacting, force accepting areas as well as said stationarypin means.

16. The improvement in accordance with claim 15 in which saidcomplimentary operative surface means includes slot means having on oneof said leg means at least a curved end wall and a bulbous surface meanson the other of said leg means adapted to broadly, but slidably, contactsaid curved end wall over at least a portion thereof and thereby permitbroad contacting, force accepting areas therebetween.

17. The improvement of claim 1 in which said pin means coincident withone of said first and second horizontal pivot axes remains stationary ata constant elevation above said top face of said ski runner until saiddisconnectably connecting cam surface means is released from said pinmeans but thereafter is adapted to change elevation with respect to saidtop face of said runner corresponding to continued angular tilting ofsaid body member relative to said base member.

18. In combination, heel binding for releasably holding a heel on a skiboot relative to a ski runner, comprising:

a. a substantially elongated base member;

b. an elongated body member having a boot-holding means, and swingablymounted to said base member at a rear pivot axis parallel to the topface of said ski runner but perpendicular to the axis of symmetrythereof, from a holding position in which said heel-holding means issubstantially abutting said top surface of said runner, to a releaseposition in which said heel-holding means is raised from and inclinedwith respect to the top face of said runner;

c. a V-frame connecting means positioned intermediate said rear pivotpoint .of said body member and said boot holding means and includingfirst and second leg means carrying complimentary cooperative surfacemeans at their swingable engaging surface to each other, said first andsecond leg means being swingable with respect to each other along afirst pivot axis substantially parallel to said rear pivot axis of saidbody member, one of said first and second leg means including asubstantially L-shaped cam surface means;

d. linking means for swingably attaching said first and second leg meansto each other along said first pivot axis, and for swingably attachingsaid first and second leg means to said body member and said base memberrespectively at second and third pivot axis parallel to said first pivotaxis, said three pivot axes being longitudinally oriented along the bodymember so as to form a V-orientation in cross section;

e. a single coil means being connected to at least one of said first andsecond leg means adapted to exert a biasing force on said first andsecond leg means to normally lock said first and second leg meansrelative to one another in a closed V-position.

f. said linking means also including latching connecting meansconnecting one of said leg means to one of said base member and saidbody member coincident with one of said second and third pivot axes, andmovable connecting means connecting the other leg means to the other ofsaid body member and said base member, as well as connecting said legmeans together coincident with said first pivot axis, said latchingconnecting means normally adapted to be positioned with respect to saidL-shaped cam surface means on said one leg means, to prevent largeexcursions of tilting of said body member relative to said base memberabout said rear pivot axis, but being adapted to release to allowangular tilting of said body member with respect to said base memberabout said rear pivot axis, when subjected to a preselected loadcondition corresponding to one of an accident condition or a manualrelease condition whereby said movable connecting means are carried inangular movement with respect to each other, initially causing said coilmeans to undergo axial compressional movement opposite to said normalbiasing force but after said L-shaped cam surface means is released fromsaid latching connecting means, said coil means undergoing reversedaxial movement in the direction of said biasing force, said movableconnecting means during bidirectional movement of said single coilmeans, defining a pair of arcuate travel, imaginary pathways (i) one ofwhich, in cross section, forms the letter S in which a first segment orloop is spaced closest to the top face of the runner whose centerformation is substantially coincident with said latching connectingmeans corresponding to said axial compressional movement of said singlecoil means, and in which a second segment or loop vertically is spaced agreater distance from the top face of the runner than said first segmentwhose center formation is coincident with said rear pivot axis of saidbody member corresponding to said reversed axial movement of said singlecoil means, and (ii) the other of which, in cross section, has a centerformation coincident with said rear pivot axis of said body member;

g. said linking means also including pivot terminating means carried onat least one of said leg means to terminate angular movement of saidmovable connecting means coincident with said first pivot horizontalaxis after its traversal of said first segment or loop of said onetravel pathway;

h. after release of said cam surface carried on said one leg means, fromsaid latching connecting means, movement of said movable connectingmeans along said pair of arcuate travel pathways being aided, at leastin part, by said bias force of said single coil means.

19. The heel binding of claim 18in which said body member is providedwith a vertical bore fitted with plunger means at a location adjacent tosaid boot holding means forward of said horizontal pivot axis, saidplunger means adapted to undergo change in elevation with respect tosaid vertical bore, utilizing said stationary pin means as a leverageapex, to contact and create said cooperative arcuate movement of saidcam surface means on said one leg means to cause said axialcompressional movement of said single coil means and release of saiddisconnectably connected cam surface means from said stationary pinmeans.

20. The heel binding of claim 18 in which said body member if furtherprovided with an inclined bore in which said single coil spring isslidably attached, a spring biasing plug means movably attached to saidbore in contact with said single coil springadapted to contact saidsingle coil spring to generate a preselected biasing force correspondingto a minimum activation level for said binding, and indicating meanscarried on said spring bias plug means, having an indexing pointerattached thereto exposed to the exterior of said body member through avertical slot in said body member, said indicating means including aconnecting pin slidably connected to a sidewall of said vertical slotmeans parallel to the longitudinal axis thereof and a numbered indexingmeans attached to spot slot means, said indexing pointer being attachedto the midpoint of said connecting pin and having a remote terminus incontact with said spring biasing plug means whereby movement of saidspring biasing plug means with respect to said single coil spring meanscauses corresponding movement of said indexing pointer with respect tosaid slot means and said indexing means.

21. in a heel binding of the type having an elongated body memberswingably mounted relative to a base member about a rearward horizontalpivot axis operative to angularly tilt from a holding position in whichsaid binding is substantially abutting the top face of the ski runner,to a release position in which the body member is inclined with respectto the top face of the runner, an improved heel holding means carried atthe forward end of said body member comprising (a) a ruggedlyconstructed flange projection extending from the forward end of saidbody member at a fixed location, in elevation, adjacent to the topsurface of said ski runner, said projection, in holding position of saidbinding forming a support floor for the sole of the ski boot, (b) aheel-supporting cleat means positioned, in elevation, above said flangeprojection in slidable contact with the end wall of said body member,(c) a less rugged laterally flared bridging platform means attached tosaid flange projection, said boot heel bridging platform means extendingfrom said flange projection and adapted, in the holding position of saidbinding, to have its top face alignable in elevation, with the topsurface of said flange projection, but over its remaining region to bepositioned in a slightly inclined relationship with respect to said skirunner, (d) pivotal connecting means for pivotally connecting said bootheel bridging platform means relative to said flange projection so as toallow said boot heel bridging platform means to pivot with respect tosaid flange projection, by gravity, as said body member tilts withrespect to said base member, the direction of rotation of said boot heelplatform being opposite to that of said body member during tiltingthereof, to a final position wherein said top face of said flangebecomes the principal support area for said heel of said ski boot.

22. The heel boot holding means of claim 21 with the addition of pivotterminating means carried on said flange projection adjacent to saidpivotal connecting means to limit rotation, by gravity, of said bootheel bridging platform means relative to said flange projection.

23. The heel-holding means of claim 22 with the addition of verticalelevating means connected between said end wall of said body member andsaid heel supporting cleat means to provide controlled vertical movementof the latter, in elevation, with respect to said flange projection tothereby accommodate ski boot heels of different thicknesses on saidheelholding means.

1. In a heel-binding of the type having forwardly extending heel-holdingmeans releasably attached to a ski boot, an elongated body memberattached to said heel holding means swingable relative to a stationarybase member adapted to be attached to a top face of a ski runner about arearward horizontal pivot axis substantially perpendicular to the axisof the ski runner but parallel to said top face of said runner, saidbody member carrying said heel holding means from a holding position inwhich said heel holding means is substantially abutting said top face ofsaid runner, to a release position in which said heel holding means israised from, and inclined with respect to said top face of said runner,the improvement comprising: a. a single coil means carried on one ofsaid body member and said base member, adapted to generate a biasingforce, along a selected zone of action; b. a V-frame connecting meanspositioned intermediate said rearward pivot axis of said body member andsaid heel-holding means in operative biasing contact with said singlecoil spring, said V-frame connecting means including first and secondleg means carrying complimentary cooperative surface means at theirswingable engaging surfaces to each other, one of said first and secondleg means including disconnectably connected cam surface means carriedon an exterior surface opposite to said single coil spring but insubstantial positional alignment with said zone of action; c. linkingmeans for connecting said first and second leg means to said body memberand said base member to the first and second horizontal pivot axis,respectively, substantially parallel to said rear pivot axis of the saidbody member, and including pin means coincident with said secondhorizontal pivot axis adapted to the position with respect to saiddisconnectably connecting cam surface means of said one leg means tonormally prevent pivotal tilting of said body member relative to thesaid base member about said rear pivot axis, but being adapted torelease when said binding is subjected to either one of two externalload conditions corresponding to (i) an accident condition or (ii) amanual release condition; d. said single coil spring means acting onsaid V-frame connecting means adapted to undergo axial compressingmovement, in dependence upon the magnitude of one of said external loadconditions applied at one or the other of said leg means to release saiddisconnectably connecting cam surface means from said pin means, bycooperative arcuate movement of said disconnectably connected camsurface means carried on said one leg means, said cooperative movementbeing in accordance with the magnitude of antibiasing forces resolvablefrom load condition along said zone of action of said single coil springmeans, said cooperative movement also causing relative angulardisplacement of said first and second leg means relative to one another;e. prior to full release of said binding, said angular relativedisplacement between said first and second leg means causing increasingdepthwise displacement of said first and second horizontal pivot axes ofsaid linking means corresponding to angular tilting of said body memberrelative to said base member about said rear pivot axis; f. afterrelease of said disconnectably connected cam surface means from said pinmeans, continued depthwise displacement of said horizontal pivot axisbeing aided, at least in part, by said normal bias force of said singlecoil spring means.
 2. The improvement in accordance with claim 1 withthe addition of pivot terminating means carried on at least one of saidleg means for terminating relative angular rotation of said first andsecond leg means after release of said pin means from operative contactwith said disconnectably connecting cam surface means.
 3. Theimprovement in accordance with claim 2 in which said linking meansincludes arcuate wall means in positional relationship with said pinmeans and adapted to allow relative rectalinear movement between saidwall means and said pin means after termination of said relative angularmovement of said first and second leg means, whereby additionaldepthwise displacement of said horizontal pivot axis is achieved so asto provide a wide-release arc for said boot-holding means, saidadditional depthwise displacement being aided, at least in part, by thenormal biasing force of said single coil spring means.
 4. Theimprovement in accordance with claim 3 in which said included arcuatewall means is an arcuate slot formed integrally within said other legmeans in capturing relationship about said pin means.
 5. The improvementin accordance with claim 2 in which said included arcuate wall means ofsaid linking means is a pair of matched arcuate slots within supportmember means attached to opposite upright sidewalls of said base memberbetween said boot-holding means and said rear pivot axis of said bindingin capturing relationship about said pin means, said pin means beingfixedly attached to said other leg means, said matched arcuate slotsadapted to allow angular rotation of said pin means followed byrectalinear travel of said pin means with respect to said matchedarcuate slots.
 6. The improvement of claim 1 in which said linking meansincludes additional pin means substantially parallel to saidfiRst-mentioned pin means, said additional pin means adapted topivotally connect said first and second leg means to each other at saidswingable engaging surfaces thereof, and under manual and accident loadconditions, adapted to undergo relative angular movement about saidfirst-mentioned pin means in conjunction with relative angular rotationof said leg means about said first and second horizontal axes, saidangular movement of said additional pin means tracing from said holdingto said release positions, a continuous arcuate imaginary pathway which,in cross section, resembles the letter ''''S.''''
 7. The improvement ofclaim 6 in which the direction of angular movement of one of said legmeans with respect to its horizontal pivot axis reverses after saiddisconnectably connecting cam surface is released from saidfirst-mentioned pin means, said reversed angular movement being aided,in part, by said biasing force of said single coil means.
 8. Theimprovement of claim 6 in which said linking means includes yet anotheradditional pin means positioned substantially parallel to saidfirst-mentioned pin means and said additional pin means and coincidentwith said first horizontal pivot axis, said yet another additional pinmeans connecting said one leg means to said body member and operative toundergo angular movement defining a pathway centered at and coincidentwith said rear pivot axis.
 9. The improvement of claim 8 in which, insaid full release position, rotation of said additional pin means isterminated prior to passage through an imaginary plane connecting saidfirst-mentioned pin means and said yet additional pin means, saidbinding being maintained in said full release positioned at least inpart by said biasing force of said single coil spring means.
 10. Theimprovement of claim 1 in which said pin means, coincident with one ofsaid first and second horizontal pivot axes, remains stationary underall load conditions of said binding at a constant elevation above saidtop face of said ski runner.
 11. The improvement of claim 10 in which,under an accident response condition, said cooperative arcuate movementof said disconnectably connected cam surface means on said one leg meanschanging the operative state of said single coil spring means forrelease of said cam surface from said stationary pin means is dependent,forcewise, on the product of the magnitude of an upward component ofexternal force applied to said linking means and the instantaneousangles of inclination existing between said stationary pin means andsaid cam surface means during said arcuate movement thereof, said upwardcomponent of external force being resolvable into said antibiasingforces acting parallel to said zone of action of said single coil springmeans having magnitudes above a selected operational release level forsaid linking means.
 12. The improvement of claim 10 in which saiddisconnectably connected cam surface means is L-shaped in cross sectionand said stationary pin means, in the holding position of said binding,is displaced, depthwise, a vertical distance ''''D'''' from engagementwith a horizontal cam surface means of said cam surface means so that,in operation of said binding, small excursions of arcuate movement ofsaid body member with respect to said base member, prior to engagementof said horizontal surface means with said stationary pin means, areallowed in dependence upon a load condition acting on one or the otherof said leg means resolvable into said antibiasing forces actingparallel to said zone of action of said coil spring means, said resolvedantibiasing forces being above at least a selected minimum activationlevel of said single coil spring means.
 13. The improvement of claim 12in which, after said stationary pin means contacts said horizontal camsurface means of said L-shaped disconnectable connecting cam surfacemeans under a load condition corresponding to a manual releasecondition, continued relative angular rotation of said lEg means forrelease of said horizontal cam surface means from said stationary pinmeans, is dependent upon the magnitude of the load resolvable into saidantibiasing force acting parallel to the zone of action of said coilspring means at either one or the other of said leg means butindependent of the angle of inclination existing between said stationarypin means and said disconnectable connected cam surface means, saidantibiasing force resulting from a leverage condition utilizing saidstationary pin means as a leverage apex so as to easily effect releaseof said horizontal cam surface means from said stationary pin means. 14.The improvement of claim 1 in which said complimentary operative surfacemeans carried on said first and second leg means, although rotatablerelative to each other, is further characterized by broad contacting,force accepting areas whereby high point stress conditions thereon dueto impingement of said antibiasing and normal biasing forces duringoperation of the binding are avoided.
 15. The improvement in accordancewith claim 14, in said holding position, in which said zone of action ofsaid coil spring means intersects said complimentary operative surfacemeans in the regions of said broad contacting, force accepting areas aswell as said stationary pin means.
 16. The improvement in accordancewith claim 15 in which said complimentary operative surface meansincludes slot means having on one of said leg means at least a curvedend wall and a bulbous surface means on the other of said leg meansadapted to broadly, but slidably, contact said curved end wall over atleast a portion thereof and thereby permit broad contacting, forceaccepting areas therebetween.
 17. The improvement of claim 1 in whichsaid pin means coincident with one of said first and second horizontalpivot axes remains stationary at a constant elevation above said topface of said ski runner until said disconnectably connecting cam surfacemeans is released from said pin means but thereafter is adapted tochange elevation with respect to said top face of said runnercorresponding to continued angular tilting of said body member relativeto said base member.
 18. In combination, heel binding for releasablyholding a heel on a ski boot relative to a ski runner, comprising: a. asubstantially elongated base member; b. an elongated body member havinga boot-holding means, and swingably mounted to said base member at arear pivot axis parallel to the top face of said ski runner butperpendicular to the axis of symmetry thereof, from a holding positionin which said heel-holding means is substantially abutting said topsurface of said runner, to a release position in which said heel-holdingmeans is raised from and inclined with respect to the top face of saidrunner; c. a V-frame connecting means positioned intermediate said rearpivot point of said body member and said boot holding means andincluding first and second leg means carrying complimentary cooperativesurface means at their swingable engaging surface to each other, saidfirst and second leg means being swingable with respect to each otheralong a first pivot axis substantially parallel to said rear pivot axisof said body member, one of said first and second leg means including asubstantially L-shaped cam surface means; d. linking means for swingablyattaching said first and second leg means to each other along said firstpivot axis, and for swingably attaching said first and second leg meansto said body member and said base member respectively at second andthird pivot axis parallel to said first pivot axis, said three pivotaxes being longitudinally oriented along the body member so as to form aV-orientation in cross section; e. a single coil means being connectedto at least one of said first and second leg means adapted to exert abiasing force on said first and second leg means to normally lock saidfirst and second leg means relative to one another in a closedV-pOsition. f. said linking means also including latching connectingmeans connecting one of said leg means to one of said base member andsaid body member coincident with one of said second and third pivotaxes, and movable connecting means connecting the other leg means to theother of said body member and said base member, as well as connectingsaid leg means together coincident with said first pivot axis, saidlatching connecting means normally adapted to be positioned with respectto said L-shaped cam surface means on said one leg means, to preventlarge excursions of tilting of said body member relative to said basemember about said rear pivot axis, but being adapted to release to allowangular tilting of said body member with respect to said base memberabout said rear pivot axis, when subjected to a preselected loadcondition corresponding to one of an accident condition or a manualrelease condition whereby said movable connecting means are carried inangular movement with respect to each other, initially causing said coilmeans to undergo axial compressional movement opposite to said normalbiasing force but after said L-shaped cam surface means is released fromsaid latching connecting means, said coil means undergoing reversedaxial movement in the direction of said biasing force, said movableconnecting means during bidirectional movement of said single coilmeans, defining a pair of arcuate travel, imaginary pathways (i) one ofwhich, in cross section, forms the letter ''''S'''' in which a firstsegment or loop is spaced closest to the top face of the runner whosecenter formation is substantially coincident with said latchingconnecting means corresponding to said axial compressional movement ofsaid single coil means, and in which a second segment or loop verticallyis spaced a greater distance from the top face of the runner than saidfirst segment whose center formation is coincident with said rear pivotaxis of said body member corresponding to said reversed axial movementof said single coil means, and (ii) the other of which, in crosssection, has a center formation coincident with said rear pivot axis ofsaid body member; g. said linking means also including pivot terminatingmeans carried on at least one of said leg means to terminate angularmovement of said movable connecting means coincident with said firstpivot horizontal axis after its traversal of said first segment or loopof said one travel pathway; h. after release of said cam surface carriedon said one leg means, from said latching connecting means, movement ofsaid movable connecting means along said pair of arcuate travel pathwaysbeing aided, at least in part, by said bias force of said single coilmeans.
 19. The heel binding of claim 18 in which said body member isprovided with a vertical bore fitted with plunger means at a locationadjacent to said boot holding means forward of said horizontal pivotaxis, said plunger means adapted to undergo change in elevation withrespect to said vertical bore, utilizing said stationary pin means as aleverage apex, to contact and create said cooperative arcuate movementof said cam surface means on said one leg means to cause said axialcompressional movement of said single coil means and release of saiddisconnectably connected cam surface means from said stationary pinmeans.
 20. The heel binding of claim 18 in which said body member iffurther provided with an inclined bore in which said single coil springis slidably attached, a spring biasing plug means movably attached tosaid bore in contact with said single coil spring adapted to contactsaid single coil spring to generate a preselected biasing forcecorresponding to a minimum activation level for said binding, andindicating means carried on said spring bias plug means, having anindexing pointer attached thereto exposed to the exterior of said bodymember through a vertical slot in said body member, said indicatingmeans including a connecting pin slidably connected tO a sidewall ofsaid vertical slot means parallel to the longitudinal axis thereof and anumbered indexing means attached to spot slot means, said indexingpointer being attached to the midpoint of said connecting pin and havinga remote terminus in contact with said spring biasing plug means wherebymovement of said spring biasing plug means with respect to said singlecoil spring means causes corresponding movement of said indexing pointerwith respect to said slot means and said indexing means.
 21. In a heelbinding of the type having an elongated body member swingably mountedrelative to a base member about a rearward horizontal pivot axisoperative to angularly tilt from a holding position in which saidbinding is substantially abutting the top face of the ski runner, to arelease position in which the body member is inclined with respect tothe top face of the runner, an improved heel holding means carried atthe forward end of said body member comprising (a) a ruggedlyconstructed flange projection extending from the forward end of saidbody member at a fixed location, in elevation, adjacent to the topsurface of said ski runner, said projection, in holding position of saidbinding forming a support floor for the sole of the ski boot, (b) aheel-supporting cleat means positioned, in elevation, above said flangeprojection in slidable contact with the end wall of said body member,(c) a less rugged laterally flared bridging platform means attached tosaid flange projection, said boot heel bridging platform means extendingfrom said flange projection and adapted, in the holding position of saidbinding, to have its top face alignable in elevation, with the topsurface of said flange projection, but over its remaining region to bepositioned in a slightly inclined relationship with respect to said skirunner, (d) pivotal connecting means for pivotally connecting said bootheel bridging platform means relative to said flange projection so as toallow said boot heel bridging platform means to pivot with respect tosaid flange projection, by gravity, as said body member tilts withrespect to said base member, the direction of rotation of said boot heelplatform being opposite to that of said body member during tiltingthereof, to a final position wherein said top face of said flangebecomes the principal support area for said heel of said ski boot. 22.The heel boot holding means of claim 21 with the addition of pivotterminating means carried on said flange projection adjacent to saidpivotal connecting means to limit rotation, by gravity, of said bootheel bridging platform means relative to said flange projection.
 23. Theheel-holding means of claim 22 with the addition of vertical elevatingmeans connected between said end wall of said body member and said heelsupporting cleat means to provide controlled vertical movement of thelatter, in elevation, with respect to said flange projection to therebyaccommodate ski boot heels of different thicknesses on said heel-holdingmeans.